The electrical conductivity and magnetic susceptibility of germanium(II) monoselenide in the solid and liquid states

The specific conductivity of germanium(II) monoselenide has been measured, under equilibrium pressure, from room temperature to 802°C. Interpretation of the results leads to the conclusion that the intrinsic conductivity is observed in the solid in the upper temperature range: the calculated energy gap is E_0g = 1.222 ± 0.027 eV which coincides with the value of the optical gap. In liquid GeSe the calculated energy gap is 1.504 ± 0.016 eV. This increase of the energy gap in liquid GeSe is due, presumably, to the strengthening of the intralayer bonds of the structure. Electrical conductivity and magnetic susceptibility measurements confirm the existence of a polymorphic transformation in GeSe at 656°C.